Interesting TLS configuration problem. Browser says "The server supports no protocols that the client advertises in the ALPN extension", and curl stops with SS

Interesting TLS configuration problem. Browser says "The server supports no protocols that the client advertises in the ALPN extension", and curl stops with SSL error. Openssl s_client does connect, reporting Peer signing digest: SHA256 Peer signature type: ECDSA Server Temp Key: X25519, 253 bits --- SSL handshake has read 4176 bytes and written 385 bytes Verification: OK --- New, TLSv1.3, Cipher is TLS_CHACHA20_POLY1305_SHA256 Any good theories what's going wrong? Is it a too discerning list of artisanal ciphers at the server end that no browser supports?